Production of threads



Sept. 26, 1939. A cERETvT PRODUCTION oF THREADS FledNov. 2, 1957 0 l 010 0 0 0 000:0 000| .000000 l0 0 0 0 0|00|000 0000A 0 O I A gri/UWM 6519677/ Patented Sept. 26, 1939 UNITED STATES PATENT or-Fica 2,174,460 raopUc'rIoN oF 'marsans Aldo Ceretti, Rome,

poration. ware Application November 2, 1937, Serial las Cor.- of Dela- In Italy December 23, 1936 1o claims.

This invention is for improvements in or relating to the production of threads and has particular though not exclusive reference to the production of threads of glass.

In U. S. A. Patent 2,081,060 there is described a method of preparing webs of glass or like materials which comprises laying the glass or like threads upon the curved surface of a rotating drum and subsequently removing the layer from the drum and subjecting it to a process of stretching.- By that process the glass threads of successive layers of the web are laid at an angle to the threads of contiguous layers, the actual angle between the threads depending upon the rate of travel of the spinning furnaces and the speed oi' rotation of the drum. In practice the threads of contiguous layers will be on the drum at an acute angle to one another or alternatively, they will take up such an arrangement upon the application of a subsequent stretching process.

It is an object of the present invention to convert a web or felt of the type .described above into a yarn or thread by a drawing process, which drawing process may be accompanied by or followed by a twisting process.

It has been found that if a comparatively thin web or lap in which the threads are arranged in a more or less regular manner intersecting only at a small angle, i. e. laid in more or less parallel arrangement be drawn in a direction transverse to the general direction of the lie of the individualV fibres, the fibres form a continuous lap of interlacing iibres in which the fibres are arranged in a general direction perpendicular to the direction in which they were arranged in the original web or lap.

The present invention accordingly comprises a process for -producing a yarn or thread which -comprises preparing a web or lapof fibresV in which the iibres are arranged so that they cross at a substantially constant angle and drawing the felt in a direction transverse to the general direction of lie of the fibres. Thus, when the threads are laid in two directions intersecting at a small angle the lap is drawn in a direction falling within the obtuse angle of intersection of the threads of the web or lap and preferably along a line bisecting the said obtuse angle.

The invention may be conveniently applied to 'strips obtained by cutting a larger lap or web at right angles to the general direction of lie of the iibres.

A web prepared by winding threads on the drum as described in the United States Patent 2,031,050

may, after removal from the drum, be cut into parallel strips as described above.

As the drawing proceeds the threads converge to form a comparatively narrow lap or strip, the precise width of the strip depending upon the I thickness and width of the original web.

During or after drawing process the strip may be subjected to a twisting process and the drawing may be accompanied by or preceded by,a spraying with a iiquid which assists the drawing 10 or twisting or imparts some desirable property to the finished product.

The invention may be applied not only to glass threads but to other iibres or mixtures of fibres which can be produced in the form of strips and u spun into threads. Again, although the web or lap of glass threads may conveniently be prepared by means of the method and apparatus described in Specification No. 2,081,060 the present invention is-not limited to the treatment of laps or webs so prepared.

The width and thickness of the web or lap, the thickness of the fibres the rate of drawing and the degree of twist may be chosen according to the count of the threads desired and the purpose for 25 which it is to be employed.

The drawing and twisting operations may be carried out by use of the known kinds of apparatus employed in the textile industry.

Among the uses to which threads and twisted 30 in accordance with the present invention may be applied may be mentioned the formation of layers which are non-inflammable and which are insulators for heat, sound and electricity.

Following is a description by way of example 35 and with reference to the accompanying drawing of one method of carrying the invention into effect.

In the drawing- Figure 1 shows in diagrammatic form apparatus of the general type described in the Patent 2,081,060 for winding glass threads on a drum.

'gure 2 shows a piece lof web produced by the apparatus shown in Figure 1,

Figures 3, 4, 5, show three strips cut from a. sheet similar to that shown in Figure 2,

Figure 6 shows in diagrammatic form apparatus for simultaneously drawing and twisting a strip of web to form a twisted yarn or thread,

Figures 7 and 8 show front and side views respectively of the winding and twisting bobbin shown in Figure 6.

Figure 9 shows the various stages in the gradual reduction of a strip to a twisted thread,

Figure 10 illustrates the direction in which the 55 strip or web is to be drawn in carrying out the present invention.

Similar reference niunerals denote similar parts throughout the figures of the drawing.

Referring to Figure 1, Il is the web obtained by winding on to the drum 2 glass threads formed with the aidof the two furnaces which are reciprocated from and to end of the drum 2 at such a speed in relation to the rate of rotation of the drum that the threads of contiguous layers are laid at an acute angle to oneV another. The threads are preferably arranged to crossat a substantially uniform angle.

In Figure 2 the material has been removed from the drum l2 and if desired subjected to a drawing process as described in Patent 2,081,060 and is cut into strips e. g. 5 by means of parallel cuts 4 tranverse to thegeneral direction of lie of the threads. 'I'he width of the strips may be varied as shown in Figure 3 according to the type of thread which it is desired to produce. In general the strips may be made to 15 centimetres wide. y

Figure 6 shows apparatus for carrying out the drawing and twisting operation on a strip or lap of web 5 and consists of tensioning rollers 6, 1 and 8 and a bobbin 9 which can be rotated about its own axis and is also capable of being rotated about an axis normal to its own axis of rotation. A toothed wheel l0 secured to the spindle of the bobin engages a crown wheel Il so that as the wheel I0 turns, the bobbin rotates about the centre of the crown wheel Il.

In practice use may be made of twisting spindles having one or two flyers of known type for the production of single or double twist.

Example A felt of glass threads produced in accordance with the process described in United States Patent 2,081,060 is cut into strips about 4 to 10 centimetres wide, the cutting of the felt taking place along the line shown in Figure 12. It will be noticed that this line intersects the obtuse angle of intersection between the threads forming the material. The strips are then drawn in the direction indicated in Figure 12; i. e. along a line bisecting the obtuse angle formed by the intersection of the threads and the yarn is drawn and spun as indicated in Figure 6, the change from web or strip to threads being that diagrammatically in Figure 9.

The strip may be sprayed with a suitable dressing before or during the drawing operation.

If the strips vof web are about 4 centimetres wide it is possible to employ bobbins similar to those employed in ldrawing frames for cotton. When strips about 'lcentimetres wide are employed bobbins similar to those used on combing machines may be employed. In the case of strips more that 10 centimetres in width simultaneous drawing and twisting of the strip will in general be carried out.

It will be understood that a yarn with a given number of filaments will be more flexible than a yarn of the same count having a smaller number of filaments of larger diameter and will therefore be more valuable.

Having now particularly described and ascertained the nature of my said invention and in whaty manner the same is to be performed, I declare that what I claim is:

1. A process for producing a yarn r thread which comprises preparing a strip of fibres crossing at a substantially constant acute angle and drawing the strip in a direction transverse to the general direction of lie of the libres.

2. A process as claimed in claim 1 wherein the strip is drawn in a direction substantially along the intersection of the obtuse angle between intersecting fibres.

3. The process of producing a strip of glass fibres which consists in helically winding a plurality of layers of glass fibres upon a winding drum the helices of each layer being arranged at an angle to preceding layers, cutting said layers lengthwise of the drum and removing the same and drawing the strip so cut in a direction substantially at right angles to the direction of lie of the fibres.

4. The process as claimed in claim 3 characterized by the fact that the strip is subjected to twisting simultaneous with the drawing thereof.

5. The process as claimed in claim 3 charto twisting simultaneous with the drawingthereof and spraying the vstrip with a liquid during the drawing thereof.

6. The process as claimed in claim 3 characterized by the fact that the strip is subjected to twisting simultaneous with the drawing thereof and spraying the strip with a liquid during the drawing and twisting thereof.

7. A process for producing a yarn which comprises preparing a web of staple length flbres arranged in a strip with the fibres extending transversely and at angles approaching a right angle to the longitudinal direction of said strip, and drawing the said strip in a longitudinal direction into a yarn.

8. A method of producing a yarn of smooth manufactured fibres which comprises preparing a web' of fibers arranged in a strip with the fibres extending transversely and at angles approaching a right angle to the longitudinal direction of said strip, and drawing the said strip in a 1ongitudinal direction into a yarn.

9. A method of producing a yarn of glass fibers which comprises winding said fibers upon a drum to form a web having the fibers arranged at angles approaching a right angle to the axial direction of said drum cutting said web in an axial direction, drawing the web in the direction substantially parallel to the direction of said cut to form a yarn.

l0. A method of producing a yarn of glass fibers which comprises winding long fine glass fibers upon a drum to form a web having at least a portion of said fibers crossing one another, cutting said web in an axial direction, and drawing the bres thereof in a direction substantially parallel to said axial cut to orient said fibers in a predominantly parallel relationship and form a yarn thereof. I

ALDO CERETTI.

i acterized by the fact that the strip is subjected 

